PHARMACOLOGICAL ACTION:Spironolactone blocks the sodium retaining action of aldosterone on the distal convoluted renal tubule, and thereby increases urinary excretion of sodium and chloride; however, it reduces excretion of potassium and ammonium and decreases the titratable acidity of urine.

INDICATIONS:Spironolactone may be used initially in the treatment of patients with oedema and ascites associated with hepatic cirrhosis to avoid depletion of potassium or precipitation of hepatic coma that may follow use of a thiazide diuretic. If more profound diuresis is necessary or in patients with congestive heart failure and the nephrotic syndrome, a thiazide or other diuretics may be given concomitantly with spironolactone.
Spironolactone may be effective in treating patients who do not respond satisfactorily to other diuretic agents but it is most useful when given with another diuretic.
Spironolactone is reported to have a hypotensive effect in patients with essential hypertension. The rise in serum potassium levels produced by spironolactone in patients with primary hyperaldosterone has been used as an aid in the diagnosis of this affliction.

CONTRA-INDICATIONS:Spironolactone is contra-indicated in patients with acute renal insufficiency, anuria and hyperkalaemia.

DOSAGE AND DIRECTIONS FOR USE:The initial dosage of 100 mg daily, in 4 divided doses. After 5 days the effect is evaluated; if the response is satisfactory the drug is continued, if possible at a lower dose. If the response is not satisfactory, a conventional diuretic may be given concomitantly at usual doses. In certain circumstances the dose of spironolactone may have to be increased to 400 mg daily. On discontinuing the drug the dose should be gradually decreased.

SIDE-EFFECTS AND SPECIAL PRECAUTIONS:Hyperkalaemia and hyponatraemia have been observed in patients treated with spironolactone. Drowsiness, headache, ataxia, coma, maculopapular or erythematous cutaneous eruptions, impotence, gynecomastia, mild androgenic effect including hirsutism, irregular menses and deepening voice may occur occasionally. Because of the risk of producing hyperkalaemia, spironolactone should be given with caution to patients with impaired renal function. It should only be given under careful supervision in patients with severe hepatic disease as stupor and transient hepatic coma may develop in these patients.
Plasma electrolyte determinations must be carried out during treatment to prevent electrolyte imbalance, especially hyponatraemia and hyperkalaemia.
Potassium supplementation in the form of either medication or a potassium-rich [diet] should not be given. Such supplementation can cause hyperkalaemia. Spironolactone may enhance the effects of other antihypertensive agents, the dose of which may need to be reduced. It should be given with caution with other potassium sparing drugs. Serum electrolytes should be estimated periodically.

KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT: The symptoms of overdosage are hyperkalaemia clinically characterised by paralysis, or muscle spasm.
Treatment is symptomatic with emphasis on potassium excretion.

CONDITIONS OF REGISTRATION:May be advertised to the profession only.

IDENTIFICATION:White bisected biconvex tablet, engraved with mortar and pestle on one side.

PRESENTATION:Packs of 30, 60, 200, 500 and 1000 tablets.

STORAGE INSTRUCTIONS:Store below 25°C. Protect from light
KEEP OUT OF REACH OF CHILDREN.

REGISTRATION NUMBER:L/18.1/186

NAME AND BUSINESS ADDRESS OF APPLICANT:Pharmacare Limited
7 Fairclough Road
Port Elizabeth
6001